Develop Reference

MouseOver effect for button in DataTemplate

I use a DataTemplate to show some buttons with a customized view (with an image, text, etc). Here is a simplified example:
<DataTemplate DataType="{x:Type viewModel:ActionItem}">
<Button Background="SlateGray" Command="{Binding Command}">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Background" Value="Green"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="DarkGoldenrod"/>
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
<TextBlock Text="{Binding Name}" />
</Button>
</DataTemplate>
Why is the mouse over effect not working at all?

Because Background="SlateGray" overrides anything you can trigger in a Style. Remove that bit and it should work.

Please set the trigger at at the template level like
<DataTemplate DataType="{x:Type viewModel:ActionItem}">
<Button Background="SlateGray" Command="{Binding Command}">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Background" Value="Green"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="DarkGoldenrod"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Button.Style>
<TextBlock Text="{Binding Name}" />
</Button>
</DataTemplate>

ToggleButton Trigger IsChecked Doesn't Change Background

I have a ToggleButton with a red background. I need to set a green background when the toggle button is checked.
I've tried this:
<ToggleButton Content="Test 001" Name="btn03" Height="20">
<ToggleButton.Style>
<Style TargetType="ToggleButton">
<Setter Property="Background" Value="#ff0000" />
<Style.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Background" Value="#00ff00" />
</Trigger>
</Style.Triggers>
</Style>
</ToggleButton.Style>
</ToggleButton>
But instead a green color I get a light blue color (I think is the default color of my
system).
What I'm doing wrong and how to fix it?

WPF 4.0 doesen't allow this. Look here for a different approach:
<Grid>
<Grid.Resources>
<Style x:Key="ToggleButtonStyle" TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border HorizontalAlignment="Center" VerticalAlignment="Center" x:Name="border" Background="Red">
<ContentPresenter/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="true">
<Setter Property="Background" TargetName="border" Value="Green"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Grid.Resources>
<ToggleButton Content="ToggleButton" Style="{StaticResource ToggleButtonStyle}"/>
</Grid>

Setter for elements inside ContentPresenter

I have a ControlTemplate like this :
<ControlTemplate TargetType="Button">
<Grid Background="Transparent">
<ContentPresenter x:Name="contentPresenter" HorizontalAlignment="Center"
VerticalAlignment="Center" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect BlurRadius="20" Color="Black" ShadowDepth="0"
Opacity="0.5" />
</Setter.Value>
</Setter>
<Setter Property="FontWeight" Value="SemiBold"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect BlurRadius="20" Color="Black" ShadowDepth="0" Opacity="1" />
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="Gray" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
When IsMouseOver property changes to True, I want all the images inside the contentPresenter to have the DropShadowEffect, not the button itself.
I tried changing the setter property to Image.Effect but it doesn't work.
How can I do it?
This is how my button looks like when Mouse is over:
And this is how it looks when it is not:
As you can see, both the Image and TextBlock is getting dropshadow effect. But I want only the Image to get it.

You can take the style recommended by Sinatr and put it in the ControlTemplate.Resources section of your button's control template. Here's an example that worked for me. It also handles the IsPressed event, during which I assume you want adjust the drop shadow effect for just the image:
<ControlTemplate x:Key="BtnTemplate" TargetType="{x:Type Button}">
<Grid Background="Transparent">
<ContentPresenter x:Name="contentPresenter" HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="FontWeight" Value="SemiBold"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="Gray" />
</Trigger>
</ControlTemplate.Triggers>
<ControlTemplate.Resources>
<Style TargetType="{x:Type Image}">
<Style.Triggers>
<DataTrigger Binding="{Binding IsMouseOver, RelativeSource={RelativeSource AncestorType=Button}}" Value="True">
<DataTrigger.Setters>
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect BlurRadius="20" Color="Black" ShadowDepth="0" Opacity="0.5"/>
</Setter.Value>
</Setter>
</DataTrigger.Setters>
</DataTrigger>
<DataTrigger Binding="{Binding IsPressed, RelativeSource={RelativeSource AncestorType=Button}}" Value="True">
<DataTrigger.Setters>
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect BlurRadius="20" Color="Black" ShadowDepth="0" Opacity="1" />
</Setter.Value>
</Setter>
</DataTrigger.Setters>
</DataTrigger>
</Style.Triggers>
</Style>
</ControlTemplate.Resources>
</ControlTemplate>

You don't really need to define Button template, rather create an Image style
<Style x:Key="style"
TargetType="Image">
<Style.Triggers>
<DataTrigger Binding="{Binding IsMouseOver, RelativeSource={RelativeSource AncestorType=Button}}"
Value="True">
<DataTrigger.Setters>
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect BlurRadius="20"
Color="Black"
ShadowDepth="0"
Opacity="0.5" />
</Setter.Value>
</Setter>
</DataTrigger.Setters>
</DataTrigger>
</Style.Triggers>
and apply it to each image you show inside button
<Button>
...
<Image Style="{StaticResource style}" ... />
...
</Button>

How to change the color of ellipse at mouse over of button WPF (c# ,wpf)

I have added an ellipse on a button.
but as of now on mouse over of that button I need to change the background.
so colould not able to do with normal trigger i.e with setting background property on mouse over event.
<Style x:Key="RButton" TargetType="Button">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse x:Name="Elipse1" Fill="Red" ></Ellipse>
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"></ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value = "Orange"/>
</Trigger>
</Style.Triggers>
</Style>

You can use TemplateBinding inside template to bind Button.Background property and set default value as another Setter of your Style
<Style x:Key="RButton" TargetType="Button">
<Setter Property="Background" Value="Red"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse x:Name="Elipse1" Fill="{TemplateBinding Background}" />
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Orange"/>
</Trigger>
</Style.Triggers>
</Style>
or, if you don't want to use Button.Background property, you can target Ellipse by name
<Setter TargetName="Elipse1" Property="Background" Value="Orange"/>

Try this Style:
<Style x:Key="RButton" TargetType="Button">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse x:Name="Elipse1" Fill="Red" ></Ellipse>
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"></ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Fill" Value = "Orange" TargetName="Elipse1" ></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Change the focus color on button when pressing tab on it

I have button with a black background. When you tab to the Button, you don't see that focus is now on the Button because of the Button's background color. How can I change the focus frame to be red?
(When you have focus on the Button, you see some frame with points in the button)
<Border x:Name="border" Background="{TemplateBinding Background}">
<ContentPresenter x:Name="contentPresenter"
ContentTemplate="{TemplateBinding ContentTemplate}"
Content="{TemplateBinding Content}"
ContentStringFormat="{TemplateBinding ContentStringFormat}"
Focusable="False"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Opacity" Value="1" />
</Trigger>
....

Try this
<Style TargetType="Button">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="FocusVisualStyle">
<Setter.Value>
<Style TargetType="Control">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle x:Name="bd" Stroke="Red" SnapsToDevicePixels="True" StrokeThickness="1" StrokeDashCap="Triangle" StrokeDashArray="1,2" Margin="1" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border x:Name="border" BorderBrush="Transparent" BorderThickness="1" Background="{TemplateBinding Background}">
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" ContentStringFormat="{TemplateBinding ContentStringFormat}" Focusable="False"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="Black"></Setter>
<Setter TargetName="border" Property="Margin" Value="1"></Setter>
</Trigger>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Foreground" Value="Red"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Button Content="Hello World" Background="Gray" Height="35" Width="200" ></Button>
Update
As per my Knowledge Elements that are not enabled do not participate in hit testing or focus and therefore will not be sources of input events.so one has to use workaround like this:
<Window.Resources>
<Style x:Key="FocusVisualStyle">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle x:Name="bd" Stroke="Red" SnapsToDevicePixels="True" StrokeThickness="1" StrokeDashCap="Triangle" StrokeDashArray="1,2" Margin="1" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Buttonstyle" TargetType="Button">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="IsEnabled" Value="True"/>
<Setter Property="FocusVisualStyle" Value="{DynamicResource FocusVisualStyle}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border x:Name="border" Focusable="False" BorderBrush="Transparent" BorderThickness="1" Background="{TemplateBinding Background}">
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" ContentStringFormat="{TemplateBinding ContentStringFormat}"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="Black"></Setter>
<Setter TargetName="border" Property="Margin" Value="1"></Setter>
</Trigger>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Foreground" Value="Red"></Setter>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Opacity" Value="0.3"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid x:Name="gd" Height="35" Width="200">
<Grid.Style>
<Style TargetType="Grid">
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=bt,Path=IsEnabled}" Value="False">
<Setter Property="Focusable" Value="True"></Setter>
<Setter Property="FocusVisualStyle" Value="{DynamicResource FocusVisualStyle}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Style>
<Button x:Name="bt" IsEnabled="False" Style="{StaticResource Buttonstyle}" Content="Hello World" IsTabStop="True" Background="Gray"/>
</Grid>

Use the IsFocused dependency property in your triggers. I suggest you to change the border width, or its colour, to differentiate the button from the unfocused ones. The dashed rectangle that indicates focus is, as far as I know, implemented in the built controls only. If you make a template, you should override it to suit your needs.